JP2005227591A - Electrostatic type actuator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a movable body from being displaced in the lateral direction and improve reliability by increasing spring force of support beams to the direction perpendicular to the direction of displacing the movable body. <P>SOLUTION: The substrate 2 is provided with almost a U-shaped support beam 6 for supporting the movable body 3 to be displaceable in the direction of the axis Y. Then, the movable body 3 is displaced from an initial position to a change-over position by the electrostatic force across electrodes 10, 11. In this case, the support beams 6 are so constructed that arm parts 7, 8 are formed in a non-parallel form when the movable body 3 is at the initial position, and the arm parts 7, 8 are stretched almost in parallel in the direction of the axis X when the movable body 3 is largely displaced up to in the neighborhood of the change-over position. Thus, since the support beams 6 can be increased in the spring force in the direction of the axis X, electrodes 10, 11 can be prevented from being short-circuited by lateral displacement when the movable body 3 is displaced, and the movable body 3 can stably be displaced in a large quantity of displacement. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electrostatic actuator suitably used for driving a movable body arranged on a substrate by an electrostatic force between electrodes, for example.

  In general, electrostatic actuators are used in optical communication parts such as optical switches, optical shutters, and optical attenuators, angular velocity sensors, resonators, and the like (see, for example, Patent Document 1).

US Pat. No. 6,229,640

  This type of conventional electrostatic actuator is formed by, for example, etching a low-resistance silicon material, a substrate, a rod-shaped movable body arranged on the substrate with a gap, and a movable substrate and A plurality of support beams provided between the body and the body so as to be able to bend and deform, and a drive unit that drives the movable body in the Y-axis direction by electrostatic force.

  Here, the movable body is formed to extend in, for example, the Y-axis direction among the X-axis and Y-axis directions orthogonal to each other. Each support beam is formed as an elongated rod-like body having springiness (elasticity), and is disposed on both sides of the movable body in the X-axis direction. The support beam has one end connected to the substrate, the other end connected to the movable body, and supports the movable body displaceable in the Y-axis direction while being separated from the substrate.

  In addition, the drive unit includes a comb-like fixed electrode provided on the substrate and a comb-like movable electrode provided on the movable body and meshing with the fixed electrode with a gap in the X-axis direction. When no voltage is applied between the fixed electrode and the movable electrode, the movable body is held at the initial position by the support beam in a free state (non-deformed state). In addition, when a voltage is applied between the fixed electrode and the movable electrode, an electrostatic force is generated between these electrodes, and each support beam is bent and deformed, so that the movable body is displaced in the Y-axis direction and has a predetermined value. Driven to the switching position.

  Thus, for example, an electrostatic actuator applied to an optical switch or the like displaces a mirror portion provided on a movable body between an initial position and a switching position, and moves the mirror portion into and out of the optical path, thereby Is switched.

  By the way, in the above-described prior art, the displacement amount when the movable body is displaced between the initial position and the switching position is set as large as possible to improve the performance and reliability of the apparatus to which the electrostatic actuator is applied. There is a demand for it. That is, for example, in an optical switch or the like, it is necessary to perform the switching operation by displacing the movable body (mirror part) larger than the aperture of the light, so that the displacement amount of the movable body is a large dimension value of, for example, 50 μm or more Often you want to set to.

  However, when the displacement amount of the movable body is simply increased, when the movable body is displaced, positional deviation, blurring, etc. easily occur in the lateral direction (X-axis direction) perpendicular to the displacement direction. Operation becomes unstable. For this reason, in the prior art, there is a limit in increasing the displacement amount of the movable body, and there is a problem that it is difficult to realize a sufficient displacement amount while maintaining the reliability of the actuator.

  In particular, when a comb-like electrode is used as the drive unit, the fixed side and movable side electrodes are engaged with each other with a minute gap. In such an actuator, even if the movable body is slightly displaced in the lateral direction, the electrodes on the fixed side and the movable side may come into contact with each other and short-circuit, and the displacement amount of the movable body is set to be excessively large. As a result, the actuator may malfunction.

  The present invention has been made in view of the above-described problems of the prior art, and an object of the present invention is to stably displace a movable body with a large amount of displacement, and prevent lateral displacement thereof. It is an object of the present invention to provide an electrostatic actuator capable of improving reliability while sufficiently securing a displacement amount of a movable body.

  In order to solve the above-described problems, the present invention provides a substrate, a movable body that is disposed on the substrate and that can be displaced in the Y-axis direction among the X-axis and Y-axis directions orthogonal to each other, and the X-axis of the movable body A plurality of support beams which are disposed on both sides in the direction so as to be able to bend and deform between the substrate and the movable body and support the movable body so as to be displaceable in the Y-axis direction; The present invention is applied to an electrostatic actuator provided with driving means for driving in an axial direction and displacing from an initial position to a switching position.

  The feature of the configuration adopted by the invention of claim 1 is that the support beam has two arm portions that extend in the X-axis direction and are spaced from each other in the Y-axis direction, and connecting portions that connect the arm portions. The arm of the support beam is held in a non-parallel shape with respect to the X-axis direction when the movable body is in the initial position, and the movable body is driven toward the switching position. In this case, the configuration extends substantially parallel to the X-axis direction.

  According to the invention of claim 2, the arm portion of the support beam is formed by a plurality of rod-like bodies extending in the X-axis direction with a space in the Y-axis direction, and the rod-like bodies are connected at different positions in the Y-axis direction. It is set as the structure connected to each part.

  According to the invention of claim 3, the width dimension in the X-axis direction of the connecting part is formed to be larger than the width dimension in the Y-axis direction of the arm part.

  According to the invention of claim 4, the width dimension in the X-axis direction of the connecting portion is configured to be larger than the width dimension in the Y-axis direction of each rod-shaped body.

  Further, according to the invention of claim 5, the arm portion of the support beam has a substrate side arm portion whose one end side is connected to the substrate and the other end side is connected to the connecting portion, and one end side which is connected to the movable body and the other end side is the substrate. The movable body side arm portion is connected to the connecting portion at a position away from the side arm portion in the Y-axis direction.

  Further, according to the invention of claim 6, the driving means includes a fixed electrode formed in a comb-like shape by a plurality of electrode plates extending in the Y-axis direction with an interval in the X-axis direction, and provided on the substrate. A plurality of electrode plates meshed with a gap between each electrode plate is formed in a comb-like shape, and is provided on a movable body, and is configured by a movable electrode that generates an electrostatic force between the fixed electrodes.

  According to the first aspect of the present invention, when the movable body is displaced from the initial position toward the switching position, the support beam can be bent and deformed. In this case, for example, when the movable body is in the vicinity of the initial position, the lateral electrostatic force (X-axis direction) applied to the movable body is relatively small, so the arm portion of the support beam has a non-parallel shape. In addition, the movable body can be stably driven in the Y-axis direction. Further, for example, when the movable body is greatly displaced, each arm portion of the support beam can be extended substantially in parallel along the X-axis direction orthogonal to the displacement direction (Y-axis direction) of the movable body. As a result, the support beam becomes nearly perpendicular to the displacement direction of the movable body, so that the spring constant in the X-axis direction of the support beam can be increased compared to the spring constant in the Y-axis direction.

  As a result, when the movable body is greatly displaced, for example, even if the asymmetric electrostatic force in the lateral direction (X-axis direction) increases, the lateral rigidity of the support beam is selectively increased so as to compensate for this. As a result, the support beam can be flexibly deformed in the displacement direction of the movable body, and the lateral displacement can be suppressed with high rigidity. Therefore, even if the displacement amount of the movable body is set large, it can be stably displaced between the initial position and the switching position, and the displacement amount of the movable body is sufficiently ensured and highly reliable. An actuator can be realized.

  According to the invention of claim 2, the arm portion of the support beam can be formed by a plurality of rod-like bodies, and these rod-like bodies can be respectively connected to the connecting portions at different positions in the Y-axis direction. Thereby, since a connection part and an arm part will be in the state connected in multiple places, the rigidity of these connection parts can be improved. Therefore, when the support beam is bent and deformed, the connecting portion can be prevented from being displaced so as to swing in the X-axis direction on the end side of the arm portion, and the rigidity of the support beam as a whole can be increased. .

  According to the invention of claim 3, the width dimension of the connecting portion can be formed larger than the width dimension of the arm portion, the rigidity of the connecting portion can be increased, and the elasticity (spring property) can be suppressed. . Thereby, when the support beam is bent and deformed, the connecting portion can be prevented from being bent and deformed in the X-axis direction, and the spring constant of the support beam in the X-axis direction can be increased.

  According to the invention of claim 4, since the width dimension of the connecting portion can be formed larger than the width dimension of each rod-like body of the arm portion, the rigidity of the connecting portion can be increased and the bending deformation in the X-axis direction can be suppressed. The spring constant in the X-axis direction of the support beam can be increased.

  According to the invention of claim 5, the support beam can be formed in a substantially U shape by the substrate side arm portion, the movable body side arm portion and the connecting portion, and the support beam is connected between the substrate and the movable body. be able to.

  Furthermore, according to the invention of claim 6, by using the comb-shaped fixed electrode and the movable electrode, it is possible to secure a sufficient facing area between the electrodes while reducing the size of each electrode, and to make the movable body a large electrostatic force. Can be driven efficiently. Since the lateral displacement of the movable body can be prevented by the support beam, a short circuit between the electrodes facing each other with a minute gap can be avoided.

  Hereinafter, an electrostatic actuator according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  Here, FIG. 1 to FIG. 6 show a first embodiment, and in this embodiment, a case where an electrostatic actuator is applied to an optical switch device will be described as an example.

  In the figure, 1 is an optical switch device, 2 is a substrate serving as a base of the optical switch device 1, and the substrate 2 is formed in a square shape of about several millimeters by a glass plate or the like, for example. It extends in the horizontal direction along the axis and the Y axis.

  Then, on the surface side of the substrate 2, for example, a low-resistance silicon material or the like is etched so that a movable body 3, a mirror unit 4, a support beam fixing unit 5, a support beam 6, a fixed electrode 10, a movable electrode, which will be described later, An electrode 11 and the like are formed.

  Reference numeral 3 denotes a movable body provided on the substrate 2. The movable body 3 is formed, for example, as an elongated rod-shaped body as shown in FIGS. 1 and 2, and extends in the Y-axis direction. The movable body 3 is supported by each support beam 6 so as to be displaceable in the Y-axis direction, and is held at a position separated from the substrate 2 together with the mirror portion 4 and the movable electrode 11.

  Reference numeral 4 denotes a mirror portion provided on the end side of the movable body 3, and the mirror portion 4 is disposed so as to be movable back and forth with respect to an optical path of an optical device 12 to be described later, and emits light emitted from the light emitting portions 12A and 12B. The optical path is switched by reflecting or passing. Moreover, the surface of the mirror part 4 is mirror-finished by forming a metal film, for example using means, such as plating, vapor deposition, and sputtering.

  As shown in FIG. 1, the mirror unit 4 is moved together with the movable body 3 by the elastic force (spring force) of each support beam 6 when no voltage is applied between the fixed electrode 10 and the movable electrode 11. At the initial position.

  When a voltage is applied between the electrodes 10 and 11, as shown in FIG. 4, the movable body 3 is driven in the Y-axis direction by the electrostatic force between the electrodes 10 and 11, and each support beam 6 is bent and deformed. . As a result, the movable body 3, the mirror unit 4 and the movable electrode 11 are displaced from the initial position to the switching position, and the optical path of the optical device 12 is switched by the mirror unit 4. In this case, the displacement amount when the movable body 3 or the like is displaced between the initial position and the switching position is set as a maximum displacement amount L, and the maximum displacement amount L is set to a large value, for example, about 60 μm.

  Reference numeral 5 denotes, for example, four support beam fixing portions projecting from the substrate 2, and each of the support beam fixing portions 5 is arranged on each side of the movable body 3 in the X-axis direction and separated in the Y-axis direction. doing. Each support beam fixing portion 5 is connected to a substrate side arm portion 7 of a support beam 6 to be described later.

  Reference numeral 6 denotes, for example, four support beams provided between the substrate 2 and the movable body 3 so as to be able to bend and deform. The support beams 6 are symmetrical with each other on both sides in the X-axis direction with the movable body 3 interposed therebetween. Are disposed at two positions with a gap in the Y-axis direction, and the movable body 3 is supported at these positions so as to be displaceable in the Y-axis direction.

  Here, the support beam 6 is formed, for example, as an elongated rod-like body bent in a substantially U-shape (rectangular shape), extends in the X-axis direction, and is disposed at intervals in the Y-axis direction. The arm portion 8 includes a connecting portion 9 that connects the two arm portions 7 and 8.

  In this case, one end side of the substrate side arm portion 7 is connected to the substrate 2 via the support beam fixing portion 5, and the other end side is connected to the connecting portion 9. The movable body side arm portion 8 has one end side connected to the movable body 3 and the other end side connected to the connecting portion 9 at a position away from the substrate side arm portion 7 in the Y-axis direction. In addition, the connecting portion 9 is formed to be bent in a substantially L shape from the other end side of the arm portions 7 and 8, and extends in the Y-axis direction.

  As shown in FIG. 3, when the movable body 3 is in the initial position, the support beam 6 is held in a free state in which no bending deformation occurs. In this free state, one end side of the arm portions 7 and 8 is closed. It is formed in a substantially U shape. At this time, each of the arm portions 7 and 8 is inclined in the Y-axis direction while extending in the X-axis direction, and one side (the movable body 3 side) with respect to the X-axis direction is the other side (the connecting portion 9 side) ) Are held in close proximity to each other. The distance between the arms 7 and 8 in the Y-axis direction is such that the distance d on one side is smaller than the distance D on the other side (D> d).

  Further, as shown in FIG. 5, the support beam 6 is bent and deformed in the Y-axis direction when the movable body 3 is driven toward the switching position, whereby each of the arm portions 7 and 8 is expanded in one end side. It is displaced to. For example, when the movable body 3 is largely displaced to the vicinity of the switching position or the like, the arm portions 7 and 8 are substantially parallel to the lateral direction (X-axis direction) orthogonal to the displacement direction (Y-axis direction) of the movable body 3. Becomes an extended state.

  As a result, the ratio of the spring constant kx in the X-axis direction to the spring constant ky in the Y-axis direction (kx / ky) of the support beam 6 is increased, and the lateral rigidity of each support beam 6 is selectively high. Become. Thus, in the present embodiment, even if the movable body 3 is largely displaced, it is possible to prevent lateral displacement and the like by the support beam 6, and the maximum displacement amount L of the movable body 3 is sufficient as described later. Can be set to size.

  Next, driving means for the movable body 3 will be described. Reference numeral 10 denotes, for example, three fixed electrodes provided on the substrate 2, and each fixed electrode 10 is formed as, for example, a comb-like electrode as shown in FIG. In addition, they are arranged symmetrically on both sides in the X-axis direction with the movable body 3 interposed therebetween, and are arranged in two places with a gap in the Y-axis direction. Each fixed electrode 10 has a plurality of electrode plates 10A extending in the Y-axis direction at intervals in the X-axis direction.

  Reference numeral 11 denotes, for example, three movable electrodes provided on the movable body 3 at positions facing each fixed electrode 10, and each movable electrode 11 constitutes a driving means together with the fixed electrode 10, and an electrode plate 10 </ b> A of the fixed electrode 10. And a plurality of electrode plates 11A meshing with gaps in the X-axis direction.

  The fixed electrode 10 and the movable electrode 11 generate an electrostatic force in the Y-axis direction between the electrode plates 10A and 11A when a voltage is applied, and the electrostatic force is generated at, for example, two locations in the Y-axis direction. By adding to the movable body 3 from both the left and right sides, the movable body 3 is displaced from the initial position to the switching position with a good balance.

  Reference numeral 12 denotes an optical device provided on the substrate 2. The optical device 12 includes light emitting portions 12A and 12B and light receiving portions 12C and 12D, as shown in FIGS. 1 and 4, and these are optical fibers (not shown). ) Etc. respectively. When the movable body 3 is in the initial position, optical paths are respectively provided between the light emitting unit 12A and the light receiving unit 12C and between the light emitting unit 12B and the light receiving unit 12D via the mirror unit 4. Further, when the movable body 3 is in the switching position, an optical path is provided outside the mirror unit 4 between the light emitting unit 12A and the light receiving unit 12D and between the light emitting unit 12B and the light receiving unit 12C. Are switched.

  The optical switch device 1 according to the present embodiment has the above-described configuration, and the operation thereof will be described next.

  First, when a voltage is applied between the fixed electrode 10 and the movable electrode 11, the electrostatic force generated between them drives the movable body 3 in the Y-axis direction against the spring force of the support beam 6. Accordingly, the movable body 3 is displaced from the initial position to the switching position while each supporting beam 6 is bent and deformed, so that the mirror unit 4 moves backward from the optical path of the optical device 12 and the optical path is switched. Further, when the voltage application is stopped, the movable body 3 is returned to the initial position by the spring force of each support beam 6, so that the mirror part 4 enters the optical path, and the optical path returns to the initial state.

  Here, the relationship between the amount of displacement of the movable body 3 and the shape of the support beam 6 will be described with reference to FIG.

  First, for example, when the movable body 3 is driven using the comb-shaped electrodes 10 and 11, the movable body 3 is caused not only by the electrostatic force in the displacement direction but also by a dimensional error of the electrode plates 10A and 11A. A lateral asymmetric electrostatic force is added. In particular, when the voltage applied between the electrodes 10 and 11 is increased in order to increase the displacement amount of the movable body 3, the movable body 3 is displaced and the opposing area in the X-axis direction between the electrode plates 10A and 11A is increased. Increases, the lateral electrostatic force becomes non-negligible compared to the spring force of the support beam 6 in the X-axis direction. As a result, when the movable body 3 is displaced laterally, the electrode plates 10A and 11A come into contact with each other and short-circuit, so that the movable body 3 cannot be displaced.

  Therefore, in order to avoid such a state, in the present embodiment, when the movable body 3 is in the initial position, the arms 7 and 8 of the support beam 6 are in a non-parallel state, and the movable body 3 is directed to the switching position. When the arm is displaced, the arm portions 7 and 8 extend substantially parallel to the lateral direction. In this configuration, the ratio (kx / ky) between the spring constant kx in the X-axis direction and the spring constant ky in the Y-axis direction of the support beam 6 depends on the displacement amount y of the movable body 3 in the Y-axis direction, for example It changes like a characteristic line 13 shown by a solid line in FIG.

  Thus, in this Embodiment, since the arm parts 7 and 8 will be in the state near perpendicular | vertical with respect to the displacement direction of the movable body 3, so that the movable body 3 is displaced largely, for example, the movable body 3 is 0-60 micrometers. When displacing over such a long distance, the ratio (kx / ky) of the spring constant of the support beam 6 can be increased according to the amount of displacement y.

  For this reason, even if the extra electrostatic force in the lateral direction increases, for example, the spring constant kx of the support beam 6 can be increased to compensate for this, and the lateral stiffness can be selectively increased. The beam 6 can be flexed and deformed smoothly in the displacement direction of the movable body 3, and the lateral displacement can be suppressed with high rigidity.

  Next, an electrostatic actuator 100 will be considered as a comparative example of the present embodiment with reference to FIG. In this case, as shown by a solid line in FIG. 7, the support beam 102 that supports the movable body 101 is, for example, substantially free of distortion between the arm portions 103 and 104 and the connecting portion 105 when the movable body 101 is in the initial position. When the movable body 101 is held in a U-shape and is displaced, it is assumed that the arms 103 and 104 are bent and deformed in the direction of expansion as indicated by phantom lines. In this comparative example, when the relationship between the displacement amount y of the movable body 101 and the ratio (kx / ky) of the spring constant of the support beam 102 is obtained, for example, a characteristic line 14 indicated by a virtual line in FIG. 6 is obtained. .

  As can be seen from the characteristic line 14, the support beam 102 is inclined with respect to the displacement direction as the movable body 101 is displaced, as in the case of the prior art (Patent Document 1). The ratio of the spring constants (kx / ky) decreases. For this reason, in the configuration of the comparative example, even when the displacement amount is, for example, about 20 to 30 μm, the movable body 101 is likely to be unable to be displaced due to a lateral displacement or the like.

  On the other hand, in this embodiment, as can be seen from the peak value of the characteristic line 13, for example, even when the maximum displacement L of the movable body 3 is set to a large dimension of about 60 μm, the displacement y is 0 to 60 μm. It was confirmed that the ratio (kx / ky) of the spring constant of the support beam 6 could be maintained at a sufficient level when the movable body 3 changed over time, and the movable body 3 could be driven stably.

  Thus, according to the present embodiment, when the movable body 3 is in the initial position, the arms 7 and 8 of the support beam 6 are held in a non-parallel shape, and the movable body 3 is driven toward the switching position. In some cases, the arm portions 7 and 8 extend substantially parallel to the X-axis direction.

  Thereby, for example, when the movable body 3 is in the vicinity of the initial position, the facing area between the electrode plates 10A and 11A of the electrodes 10 and 11 is small, and the lateral electrostatic force applied to the movable body 3 is relatively small. Since it is small, the movable body 3 can be stably driven in the Y-axis direction even if the arm portions 7 and 8 of the support beam 6 are non-parallel.

  For example, when the movable body 3 is largely displaced to the vicinity of the switching position, the arm portions 7 and 8 can be extended substantially in parallel along the X-axis direction orthogonal to the displacement direction of the movable body 3. The spring constant kx in the X-axis direction of the beam 6 can be made larger than the spring constant ky in the Y-axis direction.

  As a result, each support beam 6 can be flexibly deformed in the displacement direction of the movable body 3 and can suppress a lateral displacement of the movable body 3 with high rigidity. In this case, for example, the four support beams 6 can support the movable body 3 at two locations in the Y-axis direction from both sides in the X-axis direction with good balance, and the movable body 3 can be driven linearly in a more stable state. .

  Therefore, even if the maximum displacement amount L of the movable body 3 is set large, it can be stably displaced between the initial position and the switching position, and the displacement amount of the movable body 3 is sufficiently secured, The optical switch device 1 with high reliability can be realized.

  In addition, since the comb-shaped fixed electrode 10 and the movable electrode 11 are used as the driving means, the electrodes 10 and 11 can be reduced in size, and a sufficient opposing area can be secured between the electrodes. Can be driven efficiently. In this case, since the lateral displacement of the movable body 3 can be prevented by the support beam 6, a short circuit between the electrodes 10 and 11 facing each other with a minute gap can be avoided.

  Next, FIGS. 8 and 9 show a second embodiment according to the present invention. The feature of this embodiment is that the arm portion of the support beam is composed of a plurality of rod-shaped bodies. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  21 is an optical switch device, and the optical switch device 21 includes a substrate 2, a movable body 3, a support beam fixing portion 5, a movable electrode 11, and a support beam 22 to be described later, as in the first embodiment. It is comprised by the mirror part, the fixed electrode (not shown), etc.

  Reference numeral 22 denotes, for example, four support beams (only two are shown) that support the movable body 3 so as to be displaceable in the Y-axis direction. Each of the support beams 22 is supported on one end side in substantially the same manner as in the first embodiment. The substrate side arm portion 23 connected to the beam fixing portion 5, the movable body side arm portion 24 whose one end side is connected to the movable body 3, and a connecting portion 25 that connects these two arm portions 23, 24. ing.

  However, the substrate-side arm portion 23 is formed by, for example, two rod-like bodies 23A and 23A, and each rod-like body 23A extends in the X-axis direction with an interval in the Y-axis direction and has a width dimension in the Y-axis direction. Has W1. These rod-like bodies 23A are connected at one end side to the movable body 3 at different positions in the Y-axis direction and are connected at the other end side to the connecting portion 25 at different positions in the Y-axis direction.

  Also, the movable body side arm portion 24 is formed by, for example, two rod-like bodies 24A and 24A, which are substantially the same as the substrate side arm portion 23, and these rod-like bodies 24A have a width dimension W2 in the Y-axis direction. .

  The connecting portion 25 is formed with a width dimension W3 larger than the width dimensions W1 and W2 of the rod-like bodies 23A and 24A (W3> W1, W3> W2), and increases the rigidity of the support beam 22 in the X-axis direction. It has become.

  Thus, in the present embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment. In particular, in the present embodiment, the arm portion 23 of the support beam 22 is constituted by a plurality of rod-like bodies 23A, and the arm portion 24 is constituted by a plurality of rod-like bodies 24A.

  Thereby, in the arm part 23, each rod-shaped body 23A can be connected to the connecting part 25 at different positions in the Y-axis direction, and the connecting part 25 and the arm part 23 are connected at a plurality of locations. The rigidity of the connection part can be increased. Similarly, since the connecting portion 25 and the arm portion 24 can be connected at a plurality of locations corresponding to each rod-like body 24A, the rigidity of the connection portion can be increased.

  Therefore, when the support beam 22 is bent and deformed, the connecting portion 25 swings in the X-axis direction on the end side of the arm portions 23 and 24, for example, like a connecting portion 25 ′ indicated by an imaginary line in FIG. And the rigidity of the support beam 22 as a whole can be increased.

  Further, since the width dimension W3 of the connecting portion 25 is formed larger than the width dimensions W1 and W2 of the rod-like bodies 23A and 24A of the arm portions 23 and 24, the rigidity of the connecting portion 25 is increased and its elasticity (spring property) is increased. Can be suppressed. Thereby, when the support beam 22 is bent and deformed, the connecting portion 25 can be prevented from being bent and deformed in the X-axis direction, and the spring constant kx of the support beam 22 in the X-axis direction can be further increased. Accordingly, it is possible to more reliably prevent the displacement of the movable body 3 in the lateral direction.

  Next, FIGS. 10 and 11 show a third embodiment according to the present invention, and the feature of this embodiment is that the support beam is opened in a substantially U shape when the movable body is in the initial position. It is in the configuration. In the present embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

  31 is an optical switch device, and the optical switch device 31 is substantially the same as in the first embodiment. The optical switch device 31 includes a substrate 2, a movable body 3, a mirror section 4, a support beam fixing section 5, a fixed electrode 10 ', and a movable electrode 11. 'And a support beam 32 and the like to be described later. In the optical switch device 31, the initial position and the switching position are set opposite to those in the first embodiment, and the initial position corresponds to the switching position in the first embodiment. The position corresponds to the initial position of the first embodiment.

  Reference numeral 32 denotes, for example, four support beams that support the movable body 3 so as to be displaceable in the Y-axis direction. Each of the support beams 32 is connected to the support beam fixing portion 5 at almost one end as in the first embodiment. The substrate-side arm portion 33, one end side of which is connected to the movable body 3, and the substrate-side arm portion 33 and the movable body-side arm portion 34 extending in the X-axis direction with an interval in the Y-axis direction, and these two arm portions 33. , 34 is connected to a connecting portion 35.

  However, as shown in FIG. 10, when the movable body 3 is in the initial position, the support beam 32 is formed in a substantially U shape in which one end side of the arm portions 33 and 34 is opened, and this shape is in a free state. Yes. At this time, the arms 33 and 34 hold a non-parallel shape in which one side (the movable body 3 side) in the X-axis direction is separated from the other side (the coupling portion 35 side).

  Further, as shown in FIG. 11, the support beam 32 is bent and deformed in the Y-axis direction when the movable body 3 is driven toward the switching position, whereby the arm portions 33 and 34 are displaced in a direction in which one end side is closed. To do. For example, when the movable body 3 is largely displaced to the vicinity of the switching position or the like, the arm portions 33 and 34 are configured to extend substantially parallel to the X-axis direction.

  Thus, in the present embodiment configured as described above, it is possible to obtain substantially the same operational effects as those of the first embodiment. In particular, in the present embodiment, when the movable body 3 is in the initial position, the support beam 32 is configured in a substantially U shape with one end side of the arm portions 33 and 34 opened. When the deformation amount is set to be larger, the distance between the one end sides of the arm portions 33 and 34 can be widened at the initial position, and the shape of the support beam 32 can be avoided to avoid interference between the arm portions 33 and 34 at the initial position. Is not limited, and the degree of freedom in design can be increased.

  In the first embodiment, the support beam 6 is constituted by the arm portions 7 and 8 and the connecting portion 9 having substantially the same width. However, the present invention is not limited to this. For example, the present invention may be configured as a modification shown in FIG.

  In this case, the support beam 6 'is constituted by the substrate side arm portion 7', the movable body side arm portion 8 ', and the connecting portion 9' in substantially the same manner as in the first embodiment, but the arm portion 7 ', The width dimension W6 in the X-axis direction of the connecting portion 9 'is larger than the width dimension W4 and W5 in the Y-axis direction of 8' (W6> W4, W6> W5). In this modification, almost the same as in the second embodiment, it is possible to prevent the connecting portion 9 'from being bent and deformed in the X-axis direction, and to increase the rigidity of the support beam 6' in the X-axis direction. it can.

  In each embodiment, two support beams 6, 22, and 32 are provided on both sides of the movable body 3 in the X-axis direction. However, the present invention is not limited to this, and one support beam may be provided on each side of the movable body 3, or a plurality of three or more support beams may be provided.

  In the second embodiment, the arm portions 23 and 24 of the support beam 22 are configured by the two rod-like bodies 23A and 24A, respectively. However, the present invention is not limited to this, and the arm portion of the support beam may be constituted by three or more rod-shaped bodies.

  Furthermore, in the embodiment, the case where the electrostatic actuator is applied to the optical switch devices 1, 21, 31 has been described as an example. However, the present invention is not limited to this, and can be applied to other optical communication parts such as an optical shutter and an optical attenuator, an angular velocity sensor, a resonator, and the like.

1 is a front view showing an optical switch device according to a first embodiment of the present invention. It is the longitudinal cross-sectional view which looked at the optical switch apparatus from the arrow II-II direction in FIG. It is the elements on larger scale which show the support beam etc. in FIG. It is a front view of the optical switch apparatus which shows the state by which the movable body, the mirror part, etc. were driven from the initial position to the switching position. It is the elements on larger scale in FIG. 4 which shows the state which the support beam bent and deformed when the movable body displaced to the switching position. It is a characteristic diagram which shows the relationship between the displacement amount of a movable body, and the ratio of the spring constant of a support beam. It is the elements on larger scale which looked at the electrostatic actuator of the comparative example from the same position as FIG. It is the elements on larger scale which looked at the optical switch apparatus by the 2nd Embodiment of this invention from the same position as FIG. It is the elements on larger scale which show the state which the support beam in FIG. 8 bent and deformed. It is a front view which shows the optical switch apparatus by the 3rd Embodiment of this invention. It is a front view of the optical switch apparatus which shows the state by which the movable body, the mirror part, etc. were driven from the initial position to the switching position. It is the elements on larger scale which looked at the optical switch apparatus by the modification of this invention from the same position as FIG.

Explanation of symbols

1, 21 and 31 Optical switch device 2 Substrate 3 Movable body 4 Mirror part 5 Support beam fixing part 6, 6 ', 22, 32 Support beam 7, 7', 23, 33 Substrate side arm part 8, 8 ', 24, 34 movable body side arm part 9, 9 ', 25, 35 connecting part 10, 10' fixed electrode (drive means)
11, 11 'movable electrode (driving means)
12 Optical device 23A, 24A Bar-shaped body W1, W2, W3, W4, W5, W6 Width dimensions

Claims (6)

A substrate, a movable body that is disposed on the substrate and is movable in the Y-axis direction among the X-axis and Y-axis directions orthogonal to each other, and the substrate and the movable body that are located on both sides of the movable body in the X-axis direction And a plurality of support beams which are provided so as to be able to bend and be deformed, and are movable in the Y-axis direction, and the movable body is driven in the Y-axis direction by electrostatic force to change from the initial position to the switching position. In an electrostatic actuator having a driving means for displacing,
The support beam is formed by bending in an approximately U shape by two arm portions extending in the X-axis direction and arranged at intervals in the Y-axis direction and a connecting portion connecting the arm portions,
Each arm portion of the support beam has a non-parallel shape with respect to the X-axis direction when the movable body is in the initial position, and the X-axis direction when the movable body is driven toward the switching position. An electrostatic actuator characterized by having a configuration extending substantially in parallel with the actuator.   The arm portions of the support beam are formed by a plurality of rod-like bodies extending in the X-axis direction with a space in the Y-axis direction, and the rod-like bodies are connected to the connecting portions at different positions in the Y-axis direction. The electrostatic actuator according to claim 1.   2. The electrostatic actuator according to claim 1, wherein a width dimension of the connecting portion in the X-axis direction is formed larger than a width dimension of the arm portion in the Y-axis direction.   The electrostatic actuator according to claim 2, wherein a width dimension in the X-axis direction of the connecting portion is formed to be larger than a width dimension in the Y-axis direction of each rod-shaped body.   The arm portion of the support beam has a substrate side arm portion having one end side connected to the substrate and the other end side connected to the connecting portion, and one end side connected to the movable body and the other end side extending from the substrate side arm portion to the Y axis. 5. The electrostatic actuator according to claim 1, 2, 3, or 4, wherein the electrostatic actuator is a movable body side arm portion connected to the coupling portion at a position separated in a direction.   The driving means meshes with a gap between a fixed electrode provided on the substrate, which is formed in a comb shape by a plurality of electrode plates extending in the Y-axis direction at intervals in the X-axis direction, and each electrode plate of the fixed electrode. 6. The movable electrode according to claim 1, wherein the movable electrode is formed in a comb shape by a plurality of electrode plates and is provided on the movable body and generates an electrostatic force between the movable electrode and the fixed electrode. The electrostatic actuator described.

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